Erosion control fabrics

Erosion control fabrics n. Fabrics used in the stabilization of embankments and the containment of silt run-off from erodible slopes. In embankment stabilization, the fabric functions as a filter medium behind stabilizing rip-rap revetments. In siltation control, the fabric acts as a filter to contain silt while allowing excess water to drain freely. In turf reinforcement, the mat is used to retain soil while allowing roots and stems to grow through. In fabric-forming systems for the construction of revetments, a double-layer, water-permeable fabric is positioned, then pumped full of structural grout. These systems are alternatives to rip-rap. 

Erosion control fabrics are designed to stabilize soil on barren ground, usually slopes and hiUs. These fabrics, usually woven or nonwoven, are designed to maintain the soil and prevent its ronoval until vegetation can be established, which will prevent further erosion. Ideally, the fabrics will biodegrade so that removal of them upon restabilization of the soil, usually within six months to two years, depending upon the climate, will not be necessary. 

The mechanical properties of the various erosion control fabrics are reported in Table 11.5. Values for the standard deviation of the thickness and basis weight of the peanut fiber fabrics are unavailable. Due to the limited amount of peanut fabric produced and the fact that the webs were partially created by hand, they were tested only in one direction, labeled as the machine direction in Table 11.5. 

Table 11.5 Mechanical properties of erosion control fabrics ... 

As erosion control fabrics, the feather fiber fabrics performed almost as well as the commercially available jute and coir fabrics. It is envisioned that the peanut fibers would perform similarly to the feather fibers. Although the feather fiber and peanut fiber fabrics offer lower cost and similar performance to the commercial fabrics, they suffer in the areas of strength and stiffness, as the fabrics are somewhat weak and extremely stiff. However, blending these fibers with other natural fibers, such as cotton, and ntilizing alternative methods of bonding, snch as needlepunching, should allow for the oeation of stronger more flexible fabrics that still offer similar properties to the commercial fabrics. 

George B. R., Bockarie A., McBrideH., Hoppy D. and Scutti A. (2003), Utilization of turkey feather fibers in nonwoven erosion control fabrics , Int. Nonwovens J., 12 (2) Summer, 45-52. 

This market received a boost in the early 1990s when the EPA issued the first federal standards for municipal solid waste landfills. The main objective was to prevent leakage and protect groundwater and soil near the landfills. Needle-punched fabrics are used as a geotextile cushion specifically where there is need for puncture protection, often on top of the liner, and as blankets in drainage systems inside the landfill, as a tarpaulin on the outside of the landfill, and underneath as a foundation for erosion control. 

Research condncted with turkey feather fibers has focused on producing yams and knit fabrics containing these fibers, as weU as producing latex bonded nonwoven fabrics for use in erosion control materials. 

The wide range of end uses for these speciality fabrics, which keeps expanding, includes road paving stabilisation, landhll liners, subsurface drains, soil separation membranes, sediment control fabrics, and membranes for erosion control and weed management and suppression. 

Artificial seaweed tufted into a multifilament woven fabric was developed in 1965 by Sun Oil Co. and used to encourage sand buildup in the seabed and prevent further erosion. Both Nicolon and ICl followed with similar applications in the late 1960s (Brashears and DartneU, 1967). Silt fences, both on sloping gravel surfaces and underwater, were developed by Erosion Control Co., Burlington Industries, and the Mirafi Co. in the late 1960s (Koemer and Welsh, 1980). 

The use of natural fibre fabric is an alternative method for geo-engineering applications. The biodegradability of natural fibres has led to their use in short-term geotechnical applications to fulfil technical requirements to temporarily protect and enable the natural growth of local foliage in land and waterway reclamation, restoration or development. Natural fibres such as jute, coir, sisal, kenaf, ramie and other low-cost natural materials such as palm leaves, wood and split bamboo are also used in geotechnical applications such as erosion control, soil stabilization and soil reinforcement. 

As soil stabilization erosion control products, geotextiles minimize the impact of erosion caused by heavy rainfall and soil washing on steep, newly formed soil slopes. They absorb or store the maximum amount of water to mitigate the destructive force of surface flow and protect the soil firom erosion. Storage is achieved by a series of small dams of yam on fabrics that mn along the contour of the slope. 

The line fraction filtration test (Sansone and Koemer, 1992) can also provide valuable information about the long-term behaviour of filter fabric. In this test, the geotextile specimen is subjected to the flow of a mixture of water and soil. It may be particularly interesting for evaluating geotextile performance in silt fences in erosion control works. Palmeira and Farias (2000), eg, reported on test series in which slurries were used with soils from erosion in Brazil. The results showed that often the flow rate tended to stabilize even though conventional design would not recommend that use. 

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